Spatio-temporal-spectral observation model for urban remote sensing

Taking cities as objects being observed, urban remote sensing is an important branch of remote sensing. Given the complexity of the urban scenes, urban remote s...     

东太湖浮游植物与浮游动物群落的嵌套性及其互作网络的季节特征

浮游生物主要由浮游植物和浮游动物组成,是湖泊生态系统的重要组分.嵌套性结构及物种间的互作关系对群落的分布格局、功能乃至稳定性都具有重要意义,然而到目前为止,我们对此仍知之甚少.为此,本研究以东太湖为研究区域,在2019-2020年期间进行了春、夏、秋、冬季的观测调查,根据浮游生物群落的组成和多样性特征,结合群落分布矩阵和二分网模型研究浮游生物的嵌套性格局及其互作关系,并探讨其驱动机制.结果显示:(1)在时间上,春、秋、冬季水体的理化特征较为相似,但与夏季的水质差异显著.在空间上,西南部区域的综合污染指数显著高于东北部;(2)环境异质性使得浮游植物呈现出明显的嵌套性分布,即秋、冬季群落是春、夏季群落的子集.然而,浮游动物并未呈现该分布特征;(3)浮游生物的互作关系具有明显的季节特征:冬季的互作网络组成最简单,物种竞争最激烈,物种的特异性关系、物种脆弱性和一般性最小,说明浮游生物群落的稳定性在冬季最弱.综上所述,水环境的时空差异性造成的生态位分离可能是造成浮游生物嵌套性及其互作网络季节性变化的主要机制.     

Macroscopic criteria for Green type porous materials with spheroidal voids: application to double porous materials

Combined effects of matrix plastic compressibility and void shape are investigated for ductile porous materials. To this end, a spheroidal volume containing a confocal spheroidal (prolate or oblate) void subjected to uniform strain rate boundary conditions has been first studied. A Green type matrix is chosen as a prototype for investigating effects of plastic compressibility. This is carried out by using a kinematics limit analysis theory from which a closed‐form expression of the macroscopic criterion is established for the considered class of materials. These results are then extended to ductile porous materials made up of a green matrix containing randomly oriented spheroidal voids. In the framework of a two‐step homogenization procedure, the obtained results are implemented to describe the macroscopic behavior of double porous materials involving spherical voids at the microscale and randomly oriented and distributed spheroidal voids at the mesoscale. For validation purpose, the new derived criteria are assessed and validated by comparing their predictions to available upper bounds and numerical data from literature. Copyright © 2017 John Wiley & Sons, Ltd.     

朝鲜安州煤矿岩岩膨胀特性试验研究

In this paper, the test results of mineral component and swelling behavior of the shale at An Zhou Coal Mine, D.P.R.Korea are introduced. The results showed that the shale has properties of high unit weight, low porosity and high content of hydrophilic clay mineral. With such properties, it will have large swell and high swelling force to the support of the project. Therefore it is considered that the effective measure to prevent unstable of the surrounding rock may be reducing disturbance and changes of water content. This paper is the first achievement in cooperation research between the colleagues of our institute and Institute of Rock Mechanics Academia Korea.     

The Nadanhada Terrane

Abstract The Nadanhada terrane, a Jurassic disrupted terrane in Heilongjiang Province of China, is principally composed of Permo- Carboniferous limestone and greenstone, Triassic bedded chert and middle Jurassic siliceous shale, all enclosed within younger (presumably Late Jurassic- Early Cretaceous) clastics. Palaeontological and lithological characteristics and structural features of these formations are entirely identical to those of the Mino terrane of the Japanese Islands. Prior to opening of the Sea of Japan, these terranes formed a single superterrane together with the Western Sikhote-Alin terrane. Tectono-stratigraphic terranes very similar to the Nadanhada and Mino terranes are also found in the Ryukyu are, the Philippines and probably in Borneo. All these terranes constituted a belt of accretionary complexes during Late Jurassic and / or Early Cretaceous time along the eastern continental margin of Asia after completion of the Triassic collage of the Chinese continent.     

滇东黔西晚二叠世早期辫状河三角洲沉积体系及其聚煤特征

滇东黔西上二叠统底部发育着一套玄武岩质砾岩，本文针对云南富源和贵州盘县一带的底砾岩进行综合研究，认为这套砾岩为辫状河三角洲沉积，并进一步识别出砾质辫状河道、砂质辫状河道、砾质河口坝、砂质河口坝等沉积类型。文中还对该辫状河三角洲的沉积序列、发育背景以及与聚煤作用关系等问题做了一定分析，认为三角洲朵体之间地区以及在衰退的三角洲朵体之上成煤较好。     

华山树木年轮年表的建立

本文以秦岭东部的华山为例，论述了建立常规标准化、差值、自回归标准化这三种树木年轮年表的途径，指出了在半湿润地区利用这种途径建立树木年轮气候学年表的必要性，并进一步分析了三种年表对气候要素的响应及其差异。在取样环境较复杂的地点，建立多种年表有利于深入探讨气候要素与树木生长之间的关系，有推广的价值。     

南极乔治王岛环境质量现状调查

本文以１９９２／１９９３年度中国第九次南极考察期间对南极乔治王岛的表土、地衣、苔藓等样品的分析资料为基础，研究探讨了８种无机重金属元素、５种有机污染物的浓度水平。其结果表明，重金属在三种环境样品中的含量分布存在着明显的差异；地衣、苔藓两种植物呈现对不同重金属元素的不同富集能力；∑６６６、∑ＤＤＴ和ＰＣＢｓ及油的沾污亦很明显。本文还对污染物质的来源、南极环境样品历次调查分析的结果以及世界部分地区的背景水平进行了讨论和比较     

用非色散红外气体分析仪进行大气CO2本底浓度的测量

按WMO关于开展全球CO2监测的要求，在对引进设备进行改进的情况下，建立了我国开展大气CO2本底浓度连续测量的红外气体分析测量系统及有关方法。系统的测量精度优于0.1ppm，完全满足全球本底测量的要求，并具有较好的国际可比性。在此基础上，首次取得了我国大陆上空大气CO2的本底浓度资料。